Compressor, monitoring system, and method of monitoring compressor

Patent metadata

Field	Value
Publication number	US-11933291-B2
Application number	US-202017628466-A
Country	US
Kind code	B2
Filing date	Jul 28, 2020
Priority date	Oct 31, 2019
Publication date	Mar 19, 2024
Grant date	Mar 19, 2024

Abstract

A compressor, a monitoring system and a method of monitoring a compressor that make it possible to monitor the remaining lifetime of a semiconductor element of a motor control system while the processing load is reduced are provided. A compressor ( 1 ) includes: a motor control system ( 10 ) that controls the rotation speed of a motor ( 2 ); a compressor body ( 3 ) that compresses air by being driven by the motor ( 2 ); a pressure sensor ( 20 ) that is provided on the discharge side of the compressor body ( 3 ); and a running controller ( 11 ) that performs switching between load running and no-load running on the basis of the pressure sensed by the pressure sensor ( 20 ). A motor controller ( 26 ) of the motor control system ( 10 ) calculates a relative temperature of a semiconductor element relative to a reference temperature by using a temperature of the semiconductor element sensed by a temperature sensor ( 27 ) at the time of switching from no-load running to load running, and calculates an amount of change in a remaining lifetime of the semiconductor element corresponding to the relative temperature of the semiconductor element, whereby monitoring the remaining lifetime of the semiconductor element.

First claim

The invention claimed is:

1. A compressor comprising:
a motor;
a motor control system that controls a rotation speed of the motor;
a compressor body that compresses a gas by being driven by the motor;
a pressure sensor that is provided on a discharge side of the compressor body and senses a pressure of the compressed gas; and
a running controller that performs switching between load running and no-load running on a basis of the pressure sensed by the pressure sensor,
the motor control system having
a motor controller that controls power to be supplied to the motor via a circuit having a semiconductor element, and
a first temperature sensor that senses a temperature of the semiconductor element, wherein

at least one of the motor controller and the running controller is configured to:
calculate a relative temperature of the semiconductor element relative to a reference temperature by using the temperature sensed by the temperature sensor at time of switching from no-load running to load running; and
calculate an amount of change in a remaining lifetime of the semiconductor element corresponding to the relative temperature of the semiconductor element, whereby the remaining lifetime of the semiconductor element is monitored.

2. The compressor according to claim 1 , wherein
at least one of the motor controller and the running controller is configured to:
calculate the relative temperature of the semiconductor element relative to the reference temperature by using the temperature sensed by the first temperature sensor at time of switching of the motor from driving to stopping; and
calculate the amount of change in the remaining lifetime of the semiconductor element corresponding to the relative temperature of the semiconductor element, whereby the remaining lifetime of the semiconductor element is monitored.

3. The compressor according to claim 1 , further comprising:
a second temperature sensor that senses an air temperature around the motor control system as the reference temperature, wherein
at least one of the motor controller and the running controller is configured to calculate the relative temperature of the semiconductor element relative to the reference temperature by using the temperatures sensed by the first temperature sensor and the second temperature sensor.

4. The compressor according to claim 1 , wherein
at least one of the motor controller and the running controller is configured to output, to a display apparatus, a command for displaying information that the remaining lifetime or a consumed lifetime of the semiconductor element has reached a predetermined threshold, when the remaining lifetime or the consumed lifetime has reached the predetermined threshold.

5. The compressor according to claim 1 , wherein
the circuit having the semiconductor element is a diode circuit that converts an alternating current from a power supply into a direct current, and a power circuit that converts, into an alternating current, the direct current obtained through the conversion by the diode circuit, and that controls a frequency of the alternating current to be output to the motor.

6. A monitoring system comprising:
a compressor including a motor, a motor control system that controls a rotation speed of the motor, a compressor body that compresses a gas by being driven by the motor, a pressure sensor that is provided on a discharge side of the compressor body and senses a pressure of the compressed gas, and a running controller that performs switching between load running and no-load running on a basis of the pressure sensed by the pressure sensor, the motor control system having a motor controller that controls power to be supplied to the motor via a circuit that has a semiconductor element and having a first temperature sensor that senses a temperature of the semiconductor element; and
a monitoring server that receives, from the compressor via a communication network, a running condition of the compressor, and a sensing result of the first temperature sensor, wherein
the monitoring server is configured to:
calculate a relative temperature of the semiconductor element relative to a reference temperature by using the temperature sensed by the temperature sensor at time of switching of the compressor from no-load running to load running; and
calculate an amount of change in a remaining lifetime of the semiconductor element corresponding to the relative temperature of the semiconductor element, whereby the remaining lifetime of the semiconductor element is monitored.

7. The monitoring system according to claim 6 , wherein
the monitoring server is configured to:
calculate the relative temperature of the semiconductor element relative to the reference temperature by using the temperature sensed by the first temperature sensor at time of switching of the motor from driving to stopping; and
calculate the amount of change in the remaining lifetime of the semiconductor element corresponding to the relative temperature of the semiconductor element, whereby the remaining lifetime of the semiconductor element is monitored.

8. The monitoring system according to claim 6 , wherein
the compressor further includes a second temperature sensor that senses an air temperature around the motor control system as the reference temperature, and
the monitoring server is configured to calculate the relative temperature of the semiconductor element relative to the reference temperature by using the temperatures sensed by the first temperature sensor and the second temperature sensor.

9. The monitoring system according to claim 6 , wherein
the monitoring server is configured to transmit, to at least one of a display apparatus of the compressor and a terminal via the communication network, a command for displaying information that the remaining lifetime or a consumed lifetime of the semiconductor element has reached a predetermined threshold, when the remaining lifetime or consumed lifetime has reached the predetermined threshold.

10. The monitoring system according to claim 6 , wherein
the circuit having the semiconductor element is a diode circuit that converts an alternating current from a power supply into a direct current, and a power circuit that converts, into an alternating current, the direct current obtained through the conversion by the diode circuit, and that controls a frequency of the alternating current to be output to the motor.

11. A method of monitoring a compressor including a motor, a compressor body that compresses a gas by being driven by the motor, a pressure sensor that is provided on a discharge side of the compressor body and senses a pressure of the compressed gas, at least one controller having a functionality of switching between load running and no-load running on a basis of the pressure sensed by the pressure sensor and a functionality of controlling power to be supplied to the motor via a circuit that has a semiconductor element, and a first temperature sensor that senses a temperature of the semiconductor element, the method comprising:
calculating a relative temperature of the semiconductor element relative to a reference temperature by using the temperature sensed by the first temperature sensor at time of switching of the compressor from no-load running to load running; and
calculating an amount of change in a remaining lifetime of the semiconductor element corresponding to the relative temperature of the semiconductor element, whereby the remaining lifetime of the semiconductor element is monitored.

12. The method of monitoring the compressor according to claim 11 , comprising:
calculating the relative temperature of the semico

Assignees

• Hitachi Industry Equipment Systems Co Ltd

Inventors

• Okubo Tomofumi
• Suzuki Norinaga
• Tashima Kiyomi
• Takanuki Akihiro

Classifications

• F04B49/10 Primary

  Other safety measures · CPC title

• F04B49/02

  Stopping, starting, unloading or idling control · CPC title

• F04B49/065

  and making use of computers · CPC title

• F04B51/00

  Testing machines, pumps, or pumping installations · CPC title

• F04C28/28

  Safety arrangements; Monitoring · CPC title